what is fit
well lets look at the definition of fit
“the ability of the human body to function with vigor and alertness, without undue fatigue, and with ample energy to engage in leisure activities, and to meet physical stresses.”
Fitness is not about being thin, having a small waist, or having bulging muscles. It is a combination of qualities much the same as a farmer needs four elements for his crops to grow (soil, water, sun and air)
Physical Fitness involves Cardio Respiratory Endurance, Muscular Strength, Muscular Endurance, and Flexibility
look at in terms of a car , you have a car blowing blue smoke(oil) leaking fluids out , so its not running to its full ability
take the car in for a service make it running smoothly again
cardio and muscular excercises helps the body to use the resources that is has , air, nutrients , trains the muscles